Experiments were carried out in which potting neophytes made and fired a series of vessels under controlled conditions. The fire reached 760 degrees C after about an hour. The surface of the pit reddened to a depth of about 10 mm. Surprising weight loss of the pots was recorded, but they were weighed immediately prior to firing, so much of the weight may be lost water of plasticity. Optimum proportions of fillers could not be estimated, owing to the number of uncontrolled variables. A wide range in post-firing colors was observed, even in pots made of the same clay. Six months after the firing, seven pots showed lime spalling, while two that had been kept in a dry atmosphere showed no additional damage.